This invention relates to an improved mainsail or mizzensail cover and method that can quickly cover or uncover the mainsail of a sailboat.
More specifically, this invention relates to a sail cover and method of operation for the mainsail of a boat that is connected to the foot of the sail along the boom and, with the aid of lift lines, can be quickly utilized to cover or uncover the sail.
In the design of pleasure sailboats, the mainsail is normally supported by the main mast and has its luff or leading edge connected to a track along the mast. The foot of the mainsail is usually connected to the boom by means of a series of sliding slugs which run the length of the foot, and fits into a correspondingly shaped slot formed along the top edge of the boom. When not in use, sails such as mainsails should be stored in covers in order to prevent the sun's ultraviolet rays from gradually destroying the fabric. Conventional covers commonly in use are generally made of canvas or acrylic material, and are wrapped around the sail and the boom by using lacing cords and/or snap fittings after the mainsail has been gathered and lashed to the boom. On larger boats, installation of the cover, after the mainsail has been used, can take a number of minutes and can become a difficult task, especially in high winds or rough sea conditions. In larger boats, and where the crew is limited, the installation of the sail cover can tie up at least one crew member for five to ten minutes who otherwise might be needed for other tasks. Moreover, it is important to quickly gather the mainsail once it has been lowered onto the boom, since the mainsail can also block the view of the helmsman at a time when the boat may be navigating into a narrow harbor or through an anchorage with closely spaced together boats.
In order to quickly gather the mainsail after use, some designers have created furling mainsails with hardware not very dissimilar from that of a vertical window shade. Here, the mainsail is released from the end of the boom and furled onto a roller which is pivotably disposed parallel to the trailing edge of the main mast. In another device, the vertical furling mechanism has been installed inside of the main mast so that through the use of gears and pulleys, the sail can be pulled through a vertical, elongated slot on the trailing edge of the main mast, and be completely stored inside the hollow mast extrusion. A more recent prior art device for containing and bagging a mainsail consists of making the lower portion of the mainsail a part of the sail cover so that when the sail is lowered on the boom, its lower portion separates into two panels and permits the upper portion to be gathered between the two lower panels. A similar system called the "Zip Stop" gathers the main vertically along the mast and zips the two panels closed. This is described in U.S. Pat. No. 4,343,257. Other devices are disclosed in U.S. Pat. Nos. 3,611,969 to Hood; 3,851,609 to Stearn; 3,964,419 to Uecker; 3,980,036 to Crall; and 4,034,694 to Dismukes.
In the patent to Puretic, U.S. Pat. No. 4,354,444, there is disclosed generally triangular panels secured along the boom and a portion of the mast above the boom. The panels are designed to straddle the boom and define an open topped sail receiving pocket. This device, however, stays in its fully raised position on the boom and the mast, and cannot be collapsed out of the way when the sail is raised, nor can it be lifted back into position when the sail is to be dropped, since it does not provide for any lifting lines. In the patent to Achterberg, U.S. Pat. No. 639,916, a rigid basket or pocket is formed on both sides of the sail above the boom so that when the sail is dropped into the pocket, the basket halves can be hinged closed over the sail.
All of the above prior art methods of gathering the mainsail suffer from the disadvantage in that they are either expensive, involve complicated and unreliable hardware which is subject to exposure to open sea conditions, cannot be collapsed, distort the shape of the sail, and therefore impair the windflow across the mainsail.